In the "yes, IDists have in fact argued that IC precludes the existence of precursors with other functions" category:

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NO FOREBEARSThere seem to be no obvious evolutionary forebears in nature, and certainly no fossil record, to explain how such a machine might have been selected for through a series of random mutations in some simpler flagellum-like structures.

"If you don't have intermediate structures, it could mean one of two things, " Behe said. "Either we just haven't found them, or they are not there. It's a good bet, with these biochemical machines, that they aren't there."